An electrocardiogram (ECG) is a graphic representation of electrical activity in the heart that conveys information related to cardiac rhythms and the pumping of blood through the chambers of the heart. Electrocardiograms are also termed EKGs. The electrical activity measured relates to changes in electrical potentials during the cardiac cycle.

ECG tracing can provide information related to heart ventricle size, position, and capacity to pump blood. This information is vital to clinicians attempting to assess damage to cardiac tissue and function. Variance in electrical conduction patterns can also provide information regarding conductive patterns in the heart and can be related to abnormalities in electrically conductive concentrations of salt and mineral ions.

The heart produces weak electrical currents that can be detected by electrodes that are attached by leads to strategic monitoring locations on the surface of the body. The ECG is a passive test and the...